He asked for £20 and said he would come back the next day to finish the work.

Sibson was given the cash before leaving. The victim’s daughter then found another receipt for £20. When she asked her mother what it was for she said she had given Sibson £20 to cut her hedges. The court heard the work had not been completed. Police were contacted and Sibson was arrested. He initially tried to claim he had intended to finish the gardening work but it had been raining.

He later pleaded guilty to two offences of fraud. The court heard Sibson, of Elmete Way, Roundhay, has committed 65 previous offences, 55 of them for theft or fraud. He has served lengthy prison sentences for burglary and deception offences.

Marlon Grossman, mitigating, said Sibson’s offending was linked to his addiction to drugs.

Mr Grossman said his client was in poor health.

Jailing Sibson, judge Tom Bayliss, QC, told Sibson he must go immediately to prison because his victim was so vulnerable.

He said: “She lives alone. She has dementia. It is difficult to think of someone who is more vulnerable.

“All of that would have been apparent to you when you stole, by fraud, £40 from her.

“It is not a great sum but for a widow living on her own it is a significant amount.

“You knew what you were doing. You knew you were preying on a vulnerable individual and you had no shame in doing so.”